Developing nation is a somewhat euphemistic term referring to those nations or countries that have not achieved a significant degree of industrialization relative to their populations, and which have a low standard of living. There is a strong correlation between this status and high population growth.

Other terms sometimes used are underdeveloped nations, undeveloped nations, third-world nations, or non-industrialized nations. Conversely, the opposite end of the spectrum is termed developed nations, first-world nations, or industrialized nations.